docs: def _identify_os(self, msg):
          '''
          Using the prefix of the syslog message,
          we are able to identify the operating system and then continue parsing.
          '''
          ret = []
          for dev_os, data in self.compiled_prefixes.items():
              # TODO Should we prevent attepmting to determine the OS for the blacklisted?
              # [mircea] I think its good from a logging perspective to know at least that
              #   that the server found the matching and it tells that it won't be processed
              #   further. Later, we could potentially add an option to control this.
              log.debug('Matching under %s', dev_os)
              msg_dict = self._identify_prefix(msg, data)
              if msg_dict:
                  log.debug('Adding %s to list of matched OS', dev_os)
                  ret.append((dev_os, msg_dict))
              else:
                  log.debug('No match found for %s', dev_os)
          if not ret:
              log.debug('Not matched any OS, returning original log')
              msg_dict = {'message': msg}
              ret.append((None, msg_dict))
          return ret